Ask-A-Linguist Message Details

Subject:

A) chaplain

Question:

Hello
I have just bought a novel, Jonathan Swift's Gulliver's Travels.
There is a page about Jonathan Swift's life. There, I found a
sentence which I cannot analyze grammatically, no matter how
much I am scratching my head to come up with an answer. The
sentence is:
''At the age of thirty-one, Swift returned to Ireland as chaplain to a
lord justice.''
To me, this sentence is 100% wrong grammatically. It should be:
''At the age of thirty-one, Swift returned to Ireland as A chaplain to
a lord justice.''
Here is my reason: ''chaplain'' cannot be used without an ''A'' in
front of it because it is in singular and an ''A'' is needed in front of
it.
What do you think? Do you agree with me?
Thank you for taking the time to help me.
All the best